Does 16x/16x make a difference on a dual graphics card system?

[H]ard|OCP wanted to know just what the difference in performance was between a motherboard whose second PCIe slot runs at 8x versus one that can hit the full 16x when it has a second graphics card in it. Using an MSI X58 Eclipse which is capable of 16x with both slots populated and some tape on the second graphics card to reduce it to 8x they started benchmarking. As it turns out the difference in performance is minuscule and
that paying a large premium for a board capable of dual 16x bandwidth is not really necessary. See the results for yourself.